In the field of cabinetry and mill work a pervasive problem is uncontrolled closure of doors. Uncontrolled closure often results in slamming of cabinetry doors creating unwanted noise and premature wearing of cabinet hinges and cabinet faces. The art has responded generally to this problem by providing damping mechanisms.
Damping mechanisms are generally comprised of a spring loaded piston contained in a fluid filled cylinder for engagement with the back side of the cabinet door. In the prior art, the damping mechanism is often very close to the pivot axis of the hinge. Such placement increases the force perpendicular to the piston rod on closure of the cabinet door thereby wearing the piston rod and the seals which contain the damping fluid. Failure of the seals or the piston rod thus shortens the life cycle of the entire hinge because of the failure of the damping piston.
Premature failure is also caused by the inability of prior art hinges to adjust to the weight of the cabinet door on which they are employed.
U.S. Pat. No. 4,190,925 to Koivusalo discloses a damped hinge. A first hinge plate is attached to the door and a second to the door frame. The first hinge plate is provided with a pair of guide sleeves in which a force-transmitting rod is guided for movement in a direction parallel to the hinge axis. A helical cam attached to the second hinge plate and the piston rod follows a slot when the door swings and moves the piston rod. The piston rod is housed vertically thus adding bulk to the hinge assembly. Since the hinge is integral to the damper, failure of the damper requires replacement of the hinge. Further, the angle of contact of the hinge with the damper is extreme, leading to premature wear and failure.
U.S. Pat. No. 5,383,253 to Lin discloses a hydraulic buffer hinge. The device couples a cushion spring connected to two swinging plates with a hydraulic buffer to slow the return stroke of a swinging door. The cushion spring is aligned parallel to the pivot axis of the hinge while the piston of the hydraulic buffer is aligned perpendicularly to the pivot axis of the hinge. The damping force of the self-contained hydraulic buffer is not adjustable. Upon failure, the entire hinge assembly requires replacement.
U.S. Pat. No. 6,928,699 to Sawa discloses an automatic closing door hinge mechanism. A first wing plate includes a cylinder and a piston while a second wing plate includes an operation rod engaged with the piston. A cam is formed on the piston. An engaging part provided on the operation rod is movable in the cam. A sphere on the outer surface of the piston moves in a lengthwise groove in the cylinder to allow the piston to slide within the cylinder. Impact of the door closing is pneumatically damped within the cylinder. The apparatus is bulky and requires replacement upon failure of the piston.
Referring to FIGS. 1A and 1B, the prior art also includes “piggy back” type damper arrangement 5000 having body 5001 designed to attach to hinge arm 6001 of recessed hinge arrangement 6000. The placement of damper arrangement 5000 in the prior art is on top of hinge arm 6001 and adjacent to hinge plate 6003. The placement allows for contact of absorber 5003 with hinge plate 6003 of hinge cup 6002 for approximately 20 degrees of travel of hinge 6000 between impact position 3000 and closed position 3001. Because of the 20 degree hinge travel, the throw of absorber 5003 is extremely short and relatively ineffective at slowing the closure of a typical cabinet door. The addition of damper arrangement 5000 more than doubles the total height of hinge arm 6001 located in the cabinet thereby interfering with storage space and cabinet use.
Further, when the damper mechanism fails, the entire hinge assembly must often be replaced. Removing the entire cabinet door and replacing the hinge instead of repairing it increases the cost of replacement.
Thus, there is a need for a damper hinge device that is compact and removable.
There is also a need for a damper hinge device that extends the life cycle of the mechanism and the surrounding cabinetry.
There is also a need for a damper hinge device which is capable of contact point adjustment to provide for various applications.
It is also desirable to effectuate a damped hinge mechanism which extends the operational contact angle thereby allowing for extended contact and more effective door closure.
It is also desirable to effectuate a damper hinge mechanism with a low profile to reduce interference with operation and conserve space.